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Author SHA1 Message Date
Ben Peart
dd3551f491 fsmonitor: add a test tool to dump the index extension
Add a test utility (test-dump-fsmonitor) that will dump the fsmonitor
index extension.

Signed-off-by: Ben Peart <benpeart@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-01 17:23:05 +09:00
Ben Peart
883e248b8a fsmonitor: teach git to optionally utilize a file system monitor to speed up detecting new or changed files.
When the index is read from disk, the fsmonitor index extension is used
to flag the last known potentially dirty index entries. The registered
core.fsmonitor command is called with the time the index was last
updated and returns the list of files changed since that time. This list
is used to flag any additional dirty cache entries and untracked cache
directories.

We can then use this valid state to speed up preload_index(),
ie_match_stat(), and refresh_cache_ent() as they do not need to lstat()
files to detect potential changes for those entries marked
CE_FSMONITOR_VALID.

In addition, if the untracked cache is turned on valid_cached_dir() can
skip checking directories for new or changed files as fsmonitor will
invalidate the cache only for those directories that have been
identified as having potential changes.

To keep the CE_FSMONITOR_VALID state accurate during git operations;
when git updates a cache entry to match the current state on disk,
it will now set the CE_FSMONITOR_VALID bit.

Inversely, anytime git changes a cache entry, the CE_FSMONITOR_VALID bit
is cleared and the corresponding untracked cache directory is marked
invalid.

Signed-off-by: Ben Peart <benpeart@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-10-01 17:23:01 +09:00
Junio C Hamano
eabdcd4ab4 Merge branch 'jt/packmigrate'
Code movement to make it easier to hack later.

* jt/packmigrate: (23 commits)
  pack: move for_each_packed_object()
  pack: move has_pack_index()
  pack: move has_sha1_pack()
  pack: move find_pack_entry() and make it global
  pack: move find_sha1_pack()
  pack: move find_pack_entry_one(), is_pack_valid()
  pack: move check_pack_index_ptr(), nth_packed_object_offset()
  pack: move nth_packed_object_{sha1,oid}
  pack: move clear_delta_base_cache(), packed_object_info(), unpack_entry()
  pack: move unpack_object_header()
  pack: move get_size_from_delta()
  pack: move unpack_object_header_buffer()
  pack: move {,re}prepare_packed_git and approximate_object_count
  pack: move install_packed_git()
  pack: move add_packed_git()
  pack: move unuse_pack()
  pack: move use_pack()
  pack: move pack-closing functions
  pack: move release_pack_memory()
  pack: move open_pack_index(), parse_pack_index()
  ...
2017-08-26 22:55:09 -07:00
Junio C Hamano
030faf2fa5 Merge branch 'kw/write-index-reduce-alloc'
We used to spend more than necessary cycles allocating and freeing
piece of memory while writing each index entry out.  This has been
optimized.

* kw/write-index-reduce-alloc:
  read-cache: avoid allocating every ondisk entry when writing
  read-cache: fix memory leak in do_write_index
  perf: add test for writing the index
2017-08-26 22:55:08 -07:00
Junio C Hamano
18c88f9af6 Merge branch 'jn/vcs-svn-cleanup'
Code clean-up.

* jn/vcs-svn-cleanup:
  vcs-svn: move remaining repo_tree functions to fast_export.h
  vcs-svn: remove repo_delete wrapper function
  vcs-svn: remove custom mode constants
  vcs-svn: remove more unused prototypes and declarations
2017-08-26 22:55:06 -07:00
Jonathan Tan
4f39cd821d pack: move pack name-related functions
Currently, sha1_file.c and cache.h contain many functions, both related
to and unrelated to packfiles. This makes both files very large and
causes an unclear separation of concerns.

Create a new file, packfile.c, to hold all packfile-related functions
currently in sha1_file.c. It has a corresponding header packfile.h.

In this commit, the pack name-related functions are moved. Subsequent
commits will move the other functions.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-08-23 15:12:06 -07:00
Jonathan Nieder
b8f43b120b vcs-svn: move remaining repo_tree functions to fast_export.h
These used to be for manipulating the in-memory repo_tree structure,
but nowadays they are convenience wrappers to handle a few git-vs-svn
mismatches:

 1. Git does not track empty directories but Subversion does.  When
    looking up a path in git that Subversion thinks exists and finding
    nothing, we can safely assume that the path represents a
    directory.  This is needed when a later Subversion revision
    modifies that directory.

 2. Subversion allows deleting a file by copying.  In Git fast-import
    we have to handle that more explicitly as a deletion.

These are details of the tool's interaction with git fast-import.
Move them to fast_export.c, where other such details are handled.

This way the function names do not start with a repo_ prefix that
would clash with the repository object introduced in
v2.14.0-rc0~38^2~16 (repository: introduce the repository object,
2017-06-22) or an svn_ prefix that would clash with libsvn (in case
someone wants to link this code with libsvn some day).

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-08-23 10:41:26 -07:00
Junio C Hamano
44c2339e55 Merge branch 'mh/packed-ref-store'
The "ref-store" code reorganization continues.

* mh/packed-ref-store: (32 commits)
  files-backend: cheapen refname_available check when locking refs
  packed_ref_store: handle a packed-refs file that is a symlink
  read_packed_refs(): die if `packed-refs` contains bogus data
  t3210: add some tests of bogus packed-refs file contents
  repack_without_refs(): don't lock or unlock the packed refs
  commit_packed_refs(): remove call to `packed_refs_unlock()`
  clear_packed_ref_cache(): don't protest if the lock is held
  packed_refs_unlock(), packed_refs_is_locked(): new functions
  packed_refs_lock(): report errors via a `struct strbuf *err`
  packed_refs_lock(): function renamed from lock_packed_refs()
  commit_packed_refs(): use a staging file separate from the lockfile
  commit_packed_refs(): report errors rather than dying
  packed_ref_store: make class into a subclass of `ref_store`
  packed-backend: new module for handling packed references
  packed_read_raw_ref(): new function, replacing `resolve_packed_ref()`
  packed_ref_store: support iteration
  packed_peel_ref(): new function, extracted from `files_peel_ref()`
  repack_without_refs(): take a `packed_ref_store *` parameter
  get_packed_ref(): take a `packed_ref_store *` parameter
  rollback_packed_refs(): take a `packed_ref_store *` parameter
  ...
2017-08-22 10:29:16 -07:00
Kevin Willford
3921a0b3c3 perf: add test for writing the index
A performance test for writing the index to be able to
determine if changes to allocating ondisk structure help.

Signed-off-by: Kevin Willford <kewillf@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-08-21 15:56:53 -07:00
Junio C Hamano
a491307448 Merge branch 'jc/po-pritime-fix'
We started using "%" PRItime, imitating "%" PRIuMAX and friends, as
a way to format the internal timestamp value, but this does not
play well with gettext(1) i18n framework, and causes "make pot"
that is run by the l10n coordinator to create a broken po/git.pot
file.  This is a possible workaround for that problem.

* jc/po-pritime-fix:
  Makefile: help gettext tools to cope with our custom PRItime format
2017-07-21 14:57:37 -07:00
Junio C Hamano
e4efb39555 Merge branch 'jk/build-with-asan'
A recent update made it easier to use "-fsanitize=" option while
compiling but supported only one sanitize option.  Allow more than
one to be combined, joined with a comma, like "make SANITIZE=foo,bar".

* jk/build-with-asan:
  Makefile: allow combining UBSan with other sanitizers
2017-07-20 16:29:59 -07:00
Junio C Hamano
fc0fd5b23b Makefile: help gettext tools to cope with our custom PRItime format
We started using our own timestamp_t type and PRItime format
specifier to go along with it, so that we can later change the
underlying type and output format more easily, but this does not
play well with gettext tools.

Because gettext tools need to keep the *.po file portable across
platforms, they have to special-case the format specifiers like
PRIuMAX that are known types in inttypes.h, instead of letting CPP
handle strings like

    "%" PRIuMAX " seconds ago"

as an ordinary string concatenation.  They fundamentally cannot do
the same for our own custom type/format.

Given that po/git.pot needs to be generated only once every release
and by only one person, i.e. the l10n coordinator, let's update the
Makefile rule to generate po/git.pot so that gettext tools are run
on a munged set of sources in which all mentions of PRItime are
replaced with PRIuMAX, which is what we happen to use right now.

This way, developers do not have to care that PRItime does not play
well with gettext, and translators do not have to care that we use
our own PRItime.

The credit for the idea to munge the source files goes to Dscho.
Possible bugs are mine.

Helped-by: Jiang Xin <worldhello.net@gmail.com>
Helped-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-20 12:21:18 -07:00
René Scharfe
425ca6710b Makefile: allow combining UBSan with other sanitizers
Multiple sanitizers can be specified as a comma-separated list.  Set
the flag NO_UNALIGNED_LOADS even if UndefinedBehaviorSanitizer is not
the only sanitizer to build with.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-17 14:50:27 -07:00
Junio C Hamano
757e9874be Merge branch 'jk/build-with-asan'
The build procedure has been improved to allow building and testing
Git with address sanitizer more easily.

* jk/build-with-asan:
  Makefile: disable unaligned loads with UBSan
  Makefile: turn off -fomit-frame-pointer with sanitizers
  Makefile: add helper for compiling with -fsanitize
  test-lib: turn on ASan abort_on_error by default
  test-lib: set ASAN_OPTIONS variable before we run git
2017-07-13 16:14:54 -07:00
Junio C Hamano
2db87328ef Merge branch 'ab/sha1dc'
The "collission-detecting" implementation of SHA-1 hash we borrowed
from is replaced by directly binding the upstream project as our
submodule.  Glitches on minority platforms are still being worked out.

* ab/sha1dc:
  sha1collisiondetection: automatically enable when submodule is populated
  sha1dc: optionally use sha1collisiondetection as a submodule
2017-07-10 13:42:51 -07:00
Jeff King
566cf0b3bd Makefile: disable unaligned loads with UBSan
The undefined behavior sanitizer complains about unaligned
loads, even if they're OK for a particular platform in
practice. It's possible that they _are_ a problem, of
course, but since it's a known tradeoff the UBSan errors are
just noise.

Let's quiet it automatically by building with
NO_UNALIGNED_LOADS when SANITIZE=undefined is in use.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-10 10:02:31 -07:00
Jeff King
ddbc8a6d3e Makefile: turn off -fomit-frame-pointer with sanitizers
The ASan manual recommends disabling this optimization, as
it can make the backtraces produced by the tool harder to
follow (and since this is a test-debug build, we don't care
about squeezing out every last drop of performance).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-10 10:02:30 -07:00
Jeff King
56b5db30d0 Makefile: add helper for compiling with -fsanitize
You can already build and test with ASan by doing:

  make CFLAGS=-fsanitize=address test

but there are a few slight annoyances:

  1. It's a little long to type.

  2. It override your CFLAGS completely. You'd probably
     still want -O2, for instance.

  3. It's a good idea to also turn off "recovery", which
     lets the program keep running after a problem is
     detected (with the intention of finding as many bugs as
     possible in a given run). Since Git's test suite should
     generally run without triggering any problems, it's
     better to abort immediately and fail the test when we
     do find an issue.

With this patch, all of that happens automatically when you
run:

  make SANITIZE=address test

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-10 10:02:29 -07:00
Junio C Hamano
85ce4a6828 Merge branch 'bw/repo-object'
Introduce a "repository" object to eventually make it easier to
work in multiple repositories (the primary focus is to work with
the superproject and its submodules) in a single process.

* bw/repo-object:
  ls-files: use repository object
  repository: enable initialization of submodules
  submodule: convert is_submodule_initialized to work on a repository
  submodule: add repo_read_gitmodules
  submodule-config: store the_submodule_cache in the_repository
  repository: add index_state to struct repo
  config: read config from a repository object
  path: add repo_worktree_path and strbuf_repo_worktree_path
  path: add repo_git_path and strbuf_repo_git_path
  path: worktree_git_path() should not use file relocation
  path: convert do_git_path to take a 'struct repository'
  path: convert strbuf_git_common_path to take a 'struct repository'
  path: always pass in commondir to update_common_dir
  path: create path.h
  environment: store worktree in the_repository
  environment: place key repository state in the_repository
  repository: introduce the repository object
  environment: remove namespace_len variable
  setup: add comment indicating a hack
  setup: don't perform lazy initialization of repository state
2017-07-05 13:32:56 -07:00
Junio C Hamano
cac87dc01d sha1collisiondetection: automatically enable when submodule is populated
If a user wants to experiment with the version of collision
detecting sha1 from the submodule, the user needed to not just
populate the submodule but also needed to turn the knob.

A Makefile trick is easy enough to do so, so let's do this.  When
somebody with a copy of the submodule populated wants not to use it,
that can be done by overriding it in config.mak or from the command
line.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-03 10:09:37 -07:00
Ævar Arnfjörð Bjarmason
86cfd61e6b sha1dc: optionally use sha1collisiondetection as a submodule
Add an option to use the sha1collisiondetection library from the
submodule in sha1collisiondetection/ instead of in the copy in the
sha1dc/ directory.

This allows us to try out the submodule in sha1collisiondetection
without breaking the build for anyone who's not expecting them as we
work out any kinks.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-07-03 10:09:34 -07:00
Brandon Williams
359efeffc1 repository: introduce the repository object
Introduce the repository object 'struct repository' which can be used to
hold all state pertaining to a git repository.

Some of the benefits of object-ifying a repository are:

  1. Make the code base more readable and easier to reason about.

  2. Allow for working on multiple repositories, specifically
     submodules, within the same process.  Currently the process for
     working on a submodule involves setting up an argv_array of options
     for a particular command and then launching a child process to
     execute the command in the context of the submodule.  This is
     clunky and can require lots of little hacks in order to ensure
     correctness.  Ideally it would be nice to simply pass a repository
     and an options struct to a command.

  3. Eliminating reliance on global state will make it easier to
     enable the use of threading to improve performance.

Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-06-23 18:24:34 -07:00
Michael Haggerty
67be7c5a59 packed-backend: new module for handling packed references
Now that the interface between `files_ref_store` and
`packed_ref_store` is relatively narrow, move the latter into a new
module, "refs/packed-backend.h" and "refs/packed-backend.c". It still
doesn't quite implement the `ref_store` interface, but it will soon.

This commit moves code around and adjusts its visibility, but doesn't
change anything.

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-06-23 13:27:32 -07:00
Junio C Hamano
df7fd961a9 Merge branch 'nd/fopen-errors'
Hotfix for a topic that is already in 'master'.

* nd/fopen-errors:
  configure.ac: loosen FREAD_READS_DIRECTORIES test program
2017-06-22 14:15:20 -07:00
Junio C Hamano
ae7e4d4fed Merge branch 'ab/pcre-v2'
Update "perl-compatible regular expression" support to enable JIT
and also allow linking with the newer PCRE v2 library.

* ab/pcre-v2:
  grep: add support for PCRE v2
  grep: un-break building with PCRE >= 8.32 without --enable-jit
  grep: un-break building with PCRE < 8.20
  grep: un-break building with PCRE < 8.32
  grep: add support for the PCRE v1 JIT API
  log: add -P as a synonym for --perl-regexp
  grep: skip pthreads overhead when using one thread
  grep: don't redundantly compile throwaway patterns under threading
2017-06-19 12:38:43 -07:00
Jeff King
3adf9fdecf configure.ac: loosen FREAD_READS_DIRECTORIES test program
We added an FREAD_READS_DIRECTORIES Makefile knob long ago
in cba22528f (Add compat/fopen.c which returns NULL on
attempt to open directory, 2008-02-08) to handle systems
where reading from a directory returned garbage. This works
by catching the problem at the fopen() stage and returning
NULL.

More recently, we found that there is a class of systems
(including Linux) where fopen() succeeds but fread() fails.
Since the solution is the same (having fopen return NULL),
they use the same Makefile knob as of e2d90fd1c
(config.mak.uname: set FREAD_READS_DIRECTORIES for Linux and
FreeBSD, 2017-05-03).

This works fine except for one thing: the autoconf test in
configure.ac to set FREAD_READS_DIRECTORIES actually checks
whether fread succeeds. Which means that on Linux systems,
the knob isn't set (and we even override the config.mak.uname
default). t1308 catches the failure.

We can fix this by tweaking the autoconf test to cover both
cases. In theory we might care about the distinction between
the traditional "fread reads directories" case and the new
"fopen opens directories". But since our solution catches
the problem at the fopen stage either way, we don't actually
need to know the difference. The "fopen" case is a superset.

This does mean the FREAD_READS_DIRECTORIES name is slightly
misleading. Probably FOPEN_OPENS_DIRECTORIES would be more
accurate. But it would be disruptive to simply change the
name (people's existing build configs would fail), and it's
not worth the complexity of handling both. Let's just add a
comment in the knob description.

Reported-by: Øyvind A. Holm <sunny@sunbase.org>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-06-15 14:14:33 -07:00
Junio C Hamano
583c6a2295 Merge branch 'js/blame-lib'
The internal logic used in "git blame" has been libified to make it
easier to use by cgit.

* js/blame-lib: (29 commits)
  blame: move entry prepend to libgit
  blame: move scoreboard setup to libgit
  blame: move scoreboard-related methods to libgit
  blame: move fake-commit-related methods to libgit
  blame: move origin-related methods to libgit
  blame: move core structures to header
  blame: create entry prepend function
  blame: create scoreboard setup function
  blame: create scoreboard init function
  blame: rework methods that determine 'final' commit
  blame: wrap blame_sort and compare_blame_final
  blame: move progress updates to a scoreboard callback
  blame: make sanity_check use a callback in scoreboard
  blame: move no_whole_file_rename flag to scoreboard
  blame: move xdl_opts flags to scoreboard
  blame: move show_root flag to scoreboard
  blame: move reverse flag to scoreboard
  blame: move contents_from to scoreboard
  blame: move copy/move thresholds to scoreboard
  blame: move stat counters to scoreboard
  ...
2017-06-05 09:18:12 +09:00
Junio C Hamano
2281b8a362 Merge branch 'ab/sha1dc-maint'
The "collision detecting" SHA-1 implementation shipped with 2.13
was quite broken on some big-endian platforms and/or platforms that
do not like unaligned fetches.  Update to the upstream code which
has already fixed these issues.

* ab/sha1dc-maint:
  sha1dc: update from upstream
2017-06-04 09:55:41 +09:00
Junio C Hamano
36dcb57337 Merge branch 'ab/grep-preparatory-cleanup'
The internal implementation of "git grep" has seen some clean-up.

* ab/grep-preparatory-cleanup: (31 commits)
  grep: assert that threading is enabled when calling grep_{lock,unlock}
  grep: given --threads with NO_PTHREADS=YesPlease, warn
  pack-objects: fix buggy warning about threads
  pack-objects & index-pack: add test for --threads warning
  test-lib: add a PTHREADS prerequisite
  grep: move is_fixed() earlier to avoid forward declaration
  grep: change internal *pcre* variable & function names to be *pcre1*
  grep: change the internal PCRE macro names to be PCRE1
  grep: factor test for \0 in grep patterns into a function
  grep: remove redundant regflags assignments
  grep: catch a missing enum in switch statement
  perf: add a comparison test of log --grep regex engines with -F
  perf: add a comparison test of log --grep regex engines
  perf: add a comparison test of grep regex engines with -F
  perf: add a comparison test of grep regex engines
  perf: emit progress output when unpacking & building
  perf: add a GIT_PERF_MAKE_COMMAND for when *_MAKE_OPTS won't do
  grep: add tests to fix blind spots with \0 patterns
  grep: prepare for testing binary regexes containing rx metacharacters
  grep: add a test helper function for less verbose -f \0 tests
  ...
2017-06-02 15:06:06 +09:00
Ævar Arnfjörð Bjarmason
94da9193a6 grep: add support for PCRE v2
Add support for v2 of the PCRE API. This is a new major version of
PCRE that came out in early 2015[1].

The regular expression syntax is the same, but while the API is
similar, pretty much every function is either renamed or takes
different arguments. Thus using it via entirely new functions makes
sense, as opposed to trying to e.g. have one compile_pcre_pattern()
that would call either PCRE v1 or v2 functions.

Git can now be compiled with either USE_LIBPCRE1=YesPlease or
USE_LIBPCRE2=YesPlease, with USE_LIBPCRE=YesPlease currently being a
synonym for the former. Providing both is a compile-time error.

With earlier patches to enable JIT for PCRE v1 the performance of the
release versions of both libraries is almost exactly the same, with
PCRE v2 being around 1% slower.

However after I reported this to the pcre-dev mailing list[2] I got a
lot of help with the API use from Zoltán Herczeg, he subsequently
optimized some of the JIT functionality in v2 of the library.

Running the p7820-grep-engines.sh performance test against the latest
Subversion trunk of both, with both them and git compiled as -O3, and
the test run against linux.git, gives the following results. Just the
/perl/ tests shown:

    $ GIT_PERF_REPEAT_COUNT=30 GIT_PERF_LARGE_REPO=~/g/linux GIT_PERF_MAKE_COMMAND='grep -q LIBPCRE2 Makefile && make -j8 USE_LIBPCRE2=YesPlease CC=~/perl5/installed/bin/gcc NO_R_TO_GCC_LINKER=YesPlease CFLAGS=-O3 LIBPCREDIR=/home/avar/g/pcre2/inst LDFLAGS=-Wl,-rpath,/home/avar/g/pcre2/inst/lib || make -j8 USE_LIBPCRE=YesPlease CC=~/perl5/installed/bin/gcc NO_R_TO_GCC_LINKER=YesPlease CFLAGS=-O3 LIBPCREDIR=/home/avar/g/pcre/inst LDFLAGS=-Wl,-rpath,/home/avar/g/pcre/inst/lib' ./run HEAD~5 HEAD~ HEAD p7820-grep-engines.sh
    [...]
    Test                                            HEAD~5            HEAD~                    HEAD
    -----------------------------------------------------------------------------------------------------------------
    7820.3: perl grep 'how.to'                      0.31(1.10+0.48)   0.21(0.35+0.56) -32.3%   0.21(0.34+0.55) -32.3%
    7820.7: perl grep '^how to'                     0.56(2.70+0.40)   0.24(0.64+0.52) -57.1%   0.20(0.28+0.60) -64.3%
    7820.11: perl grep '[how] to'                   0.56(2.66+0.38)   0.29(0.95+0.45) -48.2%   0.23(0.45+0.54) -58.9%
    7820.15: perl grep '(e.t[^ ]*|v.ry) rare'       1.02(5.77+0.42)   0.31(1.02+0.54) -69.6%   0.23(0.50+0.54) -77.5%
    7820.19: perl grep 'm(ú|u)lt.b(æ|y)te'          0.38(1.57+0.42)   0.27(0.85+0.46) -28.9%   0.21(0.33+0.57) -44.7%

See commit ("perf: add a comparison test of grep regex engines",
2017-04-19) for details on the machine the above test run was executed
on.

Here HEAD~2 is git with PCRE v1 without JIT, HEAD~ is PCRE v1 with
JIT, and HEAD is PCRE v2 (also with JIT). See previous commits of mine
mentioning p7820-grep-engines.sh for more details on the test setup.

For ease of readability, a different run just of HEAD~ (PCRE v1 with
JIT v.s. PCRE v2), again with just the /perl/ tests shown:

    [...]
    Test                                            HEAD~             HEAD
    ----------------------------------------------------------------------------------------
    7820.3: perl grep 'how.to'                      0.21(0.42+0.52)   0.21(0.31+0.58) +0.0%
    7820.7: perl grep '^how to'                     0.25(0.65+0.50)   0.20(0.31+0.57) -20.0%
    7820.11: perl grep '[how] to'                   0.30(0.90+0.50)   0.23(0.46+0.53) -23.3%
    7820.15: perl grep '(e.t[^ ]*|v.ry) rare'       0.30(1.19+0.38)   0.23(0.51+0.51) -23.3%
    7820.19: perl grep 'm(ú|u)lt.b(æ|y)te'          0.27(0.84+0.48)   0.21(0.34+0.57) -22.2%

I.e. the two are either neck-to-neck, but PCRE v2 usually pulls ahead,
when it does it's around 20% faster.

A brief note on thread safety: As noted in pcre2api(3) & pcre2jit(3)
the compiled pattern can be shared between threads, but not some of
the JIT context, however the grep threading support does all pattern &
JIT compilation in separate threads, so this code doesn't need to
concern itself with thread safety.

See commit 63e7e9d8b6 ("git-grep: Learn PCRE", 2011-05-09) for the
initial addition of PCRE v1. This change follows some of the same
patterns it did (and which were discussed on list at the time),
e.g. mocking up types with typedef instead of ifdef-ing them out when
USE_LIBPCRE2 isn't defined. This adds some trivial memory use to the
program, but makes the code look nicer.

1. https://lists.exim.org/lurker/message/20150105.162835.0666407a.en.html
2. https://lists.exim.org/lurker/thread/20170419.172322.833ee099.en.html

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-06-02 08:29:05 +09:00
Ævar Arnfjörð Bjarmason
fb95e2e38d grep: un-break building with PCRE >= 8.32 without --enable-jit
Amend my change earlier in this series ("grep: add support for the
PCRE v1 JIT API", 2017-04-11) to un-break the build on PCRE v1
versions later than 8.31 compiled without --enable-jit.

As explained in that change and a later compatibility change in this
series ("grep: un-break building with PCRE < 8.32", 2017-05-10) the
pcre_jit_exec() function is a faster path to execute the JIT.

Unfortunately there's no compatibility stub for that function compiled
into the library if pcre_config(PCRE_CONFIG_JIT, &ret) would return 0,
and no macro that can be used to check for it, so the only portable
option to support builds without --enable-jit is via a new
NO_LIBPCRE1_JIT=UnfortunatelyYes Makefile option[1].

Another option would be to make the JIT opt-in via
USE_LIBPCRE1_JIT=YesPlease, after all it's not a default option of
PCRE v1.

I think it makes more sense to make it opt-out since even though it's
not a default option, most packagers of PCRE seem to turn it on by
default, with the notable exception of the MinGW package.

Make the MinGW platform work by default by changing the build defaults
to turn on NO_LIBPCRE1_JIT=UnfortunatelyYes. It is the only platform
that turns on USE_LIBPCRE=YesPlease by default, see commit
df5218b4c3 ("config.mak.uname: support MSys2", 2016-01-13) for that
change.

1. "How do I support pcre1 JIT on all
   versions?"  (https://lists.exim.org/lurker/thread/20170601.103148.10253788.en.html)

2. https://github.com/Alexpux/MINGW-packages/blob/master/mingw-w64-pcre/PKGBUILD
   (referenced from "Re: PCRE v2 compile error, was Re: What's cooking
   in git.git (May 2017, #01; Mon, 1)";
   <alpine.DEB.2.20.1705021756530.3480@virtualbox>)

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-06-02 08:29:05 +09:00
Junio C Hamano
ae7785de0e Merge branch 'bp/sub-process-convert-filter'
Code from "conversion using external process" codepath has been
extracted to a separate sub-process.[ch] module.

* bp/sub-process-convert-filter:
  convert: update subprocess_read_status() to not die on EOF
  sub-process: move sub-process functions into separate files
  convert: rename reusable sub-process functions
  convert: update generic functions to only use generic data structures
  convert: separate generic structures and variables from the filter specific ones
  convert: split start_multi_file_filter() into two separate functions
  pkt-line: annotate packet_writel with LAST_ARG_MUST_BE_NULL
  convert: move packet_write_line() into pkt-line as packet_writel()
  pkt-line: add packet_read_line_gently()
  pkt-line: fix packet_read_line() to handle len < 0 errors
  convert: remove erroneous tests for errno == EPIPE
2017-05-30 11:16:42 +09:00
Ævar Arnfjörð Bjarmason
68c7d2761d test-lib: add a PTHREADS prerequisite
Add a PTHREADS prerequisite which is false when git is compiled with
NO_PTHREADS=YesPlease.

There's lots of custom code that runs when threading isn't available,
but before this prerequisite there was no way to test it.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-05-26 12:52:37 +09:00
Ævar Arnfjörð Bjarmason
3485bea157 grep: change the internal PCRE macro names to be PCRE1
Change the internal USE_LIBPCRE define, & build options flag to use a
naming convention ending in PCRE1, without changing the long-standing
USE_LIBPCRE Makefile flag which enables this code.

This is for preparation for libpcre2 support where having things like
USE_LIBPCRE and USE_LIBPCRE2 in any more places than we absolutely
need to for backwards compatibility with old Makefile arguments would
be confusing.

In some ways it would be better to change everything that now uses
USE_LIBPCRE to use USE_LIBPCRE1, and to make specifying
USE_LIBPCRE (or --with-pcre) an error. This would impose a one-time
burden on packagers of git to s/USE_LIBPCRE/USE_LIBPCRE1/ in their
build scripts.

However I'd like to leave the door open to making
USE_LIBPCRE=YesPlease eventually mean USE_LIBPCRE2=YesPlease,
i.e. once PCRE v2 is ubiquitous enough that it makes sense to make it
the default.

This code and the USE_LIBPCRE Makefile argument was added in commit
63e7e9d8b6 ("git-grep: Learn PCRE", 2011-05-09). At the time there was
no indication that the PCRE project would release an entirely new &
incompatible API around 3 years later.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-05-26 12:52:37 +09:00
Jeff Smith
f5dd754c36 blame: move origin-related methods to libgit
Signed-off-by: Jeff Smith <whydoubt@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-05-25 13:08:22 +09:00
Ævar Arnfjörð Bjarmason
a0103914c2 sha1dc: update from upstream
Update sha1dc from the latest version by the upstream
maintainer[1].

This version includes a commit of mine which allows for replacing the
local modifications done to the upstream files in git.git with macro
definitions to monkeypatch it in place.

It also brings in a change[2] upstream made for the breakage 2.13.0
introduced on SPARC and other platforms that forbid unaligned
access[3].

This means that the code customizations done since the initial import
in commit 28dc98e343 ("sha1dc: add collision-detecting sha1
implementation", 2017-03-16) can be done purely via Makefile
definitions and by including the content of our own sha1dc_git.[ch] in
sha1dc/sha1.c via a macro.

1. cc465543b3
2. 33a694a9ee
3. "Git 2.13.0 segfaults on Solaris SPARC due to DC_SHA1=YesPlease
   being on by default"
   (https://public-inbox.org/git/CACBZZX6nmKK8af0-UpjCKWV4R+hV-uk2xWXVA5U+_UQ3VXU03g@mail.gmail.com/)

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-05-22 10:20:46 +09:00
Ævar Arnfjörð Bjarmason
88b6197d0b perf: add a GIT_PERF_MAKE_COMMAND for when *_MAKE_OPTS won't do
Add a git GIT_PERF_MAKE_COMMAND variable to compliment the existing
GIT_PERF_MAKE_OPTS facility. This allows specifying an arbitrary shell
command to execute instead of 'make'.

This is useful e.g. in cases where the name, semantics or defaults of
a Makefile flag have changed over time. It can even be used to change
the contents of the tree, useful for monkeypatching ancient versions
of git to get them to build.

This opens Pandora's box in some ways, it's now possible to
"jailbreak" the perf environment and e.g. modify the source tree via
this arbitrary instead of just issuing a custom "make" command, such a
command has to be re-entrant in the sense that subsequent perf runs
will re-use the possibly modified tree.

It would be pointless to try to mitigate or work around that caveat in
a tool purely aimed at Git developers, so this change makes no attempt
to do so.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-05-21 08:25:38 +09:00
Ævar Arnfjörð Bjarmason
072473e659 Makefile & configure: reword inaccurate comment about PCRE
Reword an outdated & inaccurate comment which suggests that only
git-grep can use PCRE.

This comment was added back when PCRE support was initially added in
commit 63e7e9d8b6 ("git-grep: Learn PCRE", 2011-05-09), and was true
at the time.

It hasn't been telling the full truth since git-log learned to use
PCRE with --grep in commit 727b6fc3ed ("log --grep: accept
--basic-regexp and --perl-regexp", 2012-10-03), and more importantly
is likely to get more inaccurate over time as more use is made of PCRE
in other areas.

Reword it to be more future-proof, and to more clearly explain that
this enables user-initiated runtime behavior.

Copy/pasting this so much in configure.ac is lame, these Makefile-like
flags aren't even used by autoconf, just the corresponding
--with[out]-* options. But copy/pasting the comments that make sense
for the Makefile to configure.ac where they make less sense is the
pattern everything else follows in that file. I'm not going to war
against that as part of this change, just following the existing
pattern.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-05-21 08:25:37 +09:00
Ben Peart
99605d62e8 sub-process: move sub-process functions into separate files
Move the sub-proces functions into sub-process.h/c.  Add documentation
for the new module in Documentation/technical/api-sub-process.txt

Signed-off-by: Ben Peart <benpeart@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-05-15 13:01:57 +09:00
Junio C Hamano
77b34eaa07 Merge branch 'mh/separate-ref-cache'
The internals of the refs API around the cached refs has been
streamlined.

* mh/separate-ref-cache:
  do_for_each_entry_in_dir(): delete function
  files_pack_refs(): use reference iteration
  commit_packed_refs(): use reference iteration
  cache_ref_iterator_begin(): make function smarter
  get_loose_ref_cache(): new function
  get_loose_ref_dir(): function renamed from get_loose_refs()
  do_for_each_entry_in_dir(): eliminate `offset` argument
  refs: handle "refs/bisect/" in `loose_fill_ref_dir()`
  ref-cache: use a callback function to fill the cache
  refs: record the ref_store in ref_cache, not ref_dir
  ref-cache: introduce a new type, ref_cache
  refs: split `ref_cache` code into separate files
  ref-cache: rename `remove_entry()` to `remove_entry_from_dir()`
  ref-cache: rename `find_ref()` to `find_ref_entry()`
  ref-cache: rename `add_ref()` to `add_ref_entry()`
  refs_verify_refname_available(): use function in more places
  refs_verify_refname_available(): implement once for all backends
  refs_ref_iterator_begin(): new function
  refs_read_raw_ref(): new function
  get_ref_dir(): don't call read_loose_refs() for "refs/bisect"
2017-04-26 15:39:13 +09:00
Junio C Hamano
6cbc478d83 Merge branch 'jh/add-index-entry-optim'
"git checkout" that handles a lot of paths has been optimized by
reducing the number of unnecessary checks of paths in the
has_dir_name() function.

* jh/add-index-entry-optim:
  read-cache: speed up has_dir_name (part 2)
  read-cache: speed up has_dir_name (part 1)
  read-cache: speed up add_index_entry during checkout
  p0006-read-tree-checkout: perf test to time read-tree
  read-cache: add strcmp_offset function
2017-04-26 15:39:07 +09:00
Junio C Hamano
8377f34540 Merge branch 'jh/memihash-opt'
Hotfix for a topic that is already in 'master'.

* jh/memihash-opt:
  p0004: make perf test executable
  t3008: skip lazy-init test on a single-core box
  test-online-cpus: helper to return cpu count
  name-hash: fix buffer overrun
2017-04-19 21:37:25 -07:00
Junio C Hamano
5ab8f2261f Merge branch 'nd/files-backend-git-dir'
The "submodule" specific field in the ref_store structure is
replaced with a more generic "gitdir" that can later be used also
when dealing with ref_store that represents the set of refs visible
from the other worktrees.

* nd/files-backend-git-dir: (28 commits)
  refs.h: add a note about sorting order of for_each_ref_*
  t1406: new tests for submodule ref store
  t1405: some basic tests on main ref store
  t/helper: add test-ref-store to test ref-store functions
  refs: delete pack_refs() in favor of refs_pack_refs()
  files-backend: avoid ref api targeting main ref store
  refs: new transaction related ref-store api
  refs: add new ref-store api
  refs: rename get_ref_store() to get_submodule_ref_store() and make it public
  files-backend: replace submodule_allowed check in files_downcast()
  refs: move submodule code out of files-backend.c
  path.c: move some code out of strbuf_git_path_submodule()
  refs.c: make get_main_ref_store() public and use it
  refs.c: kill register_ref_store(), add register_submodule_ref_store()
  refs.c: flatten get_ref_store() a bit
  refs: rename lookup_ref_store() to lookup_submodule_ref_store()
  refs.c: introduce get_main_ref_store()
  files-backend: remove the use of git_path()
  files-backend: add and use files_ref_path()
  files-backend: add and use files_reflog_path()
  ...
2017-04-19 21:37:19 -07:00
Junio C Hamano
3817d631de Merge branch 'ab/regen-perl-mak-with-different-perl'
Update the build dependency so that an update to /usr/bin/perl
etc. result in recomputation of perl.mak file.

* ab/regen-perl-mak-with-different-perl:
  perl: regenerate perl.mak if perl -V changes
2017-04-16 23:29:33 -07:00
Michael Haggerty
958f964691 refs: split ref_cache code into separate files
The `ref_cache` code is currently too tightly coupled to
`files-backend`, making the code harder to understand and making it
awkward for new code to use `ref_cache` (as we indeed have planned).
Start loosening that coupling by splitting `ref_cache` into a separate
module.

This commit moves code, adds declarations, and changes the visibility
of some functions, but doesn't change any code.

The modules are still too tightly coupled, but the situation will be
improved in subsequent commits.

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-04-16 21:32:45 -07:00
Jeff Hostetler
a6db3fbb6e read-cache: add strcmp_offset function
Add strcmp_offset() function to also return the offset of the
first change.

Add unit test and helper to verify.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-04-15 02:21:12 -07:00
Nguyễn Thái Ngọc Duy
80f2a6097c t/helper: add test-ref-store to test ref-store functions
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-04-14 03:53:25 -07:00
Jeff Hostetler
e3482ccf27 test-online-cpus: helper to return cpu count
Created helper executable to print the value of online_cpus()
allowing multi-threaded tests to be skipped when appropriate.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-04-12 23:17:19 -07:00
Junio C Hamano
876eb616d3 Merge branch 'jk/make-coccicheck-detect-errors'
Build fix.

* jk/make-coccicheck-detect-errors:
  Makefile: detect errors in running spatch
2017-03-30 14:07:19 -07:00
Ævar Arnfjörð Bjarmason
c59c4939c2 perl: regenerate perl.mak if perl -V changes
Change the perl/perl.mak build process so that the file is regenerated
if the output of "perl -V" changes.

Before this change updating e.g. /usr/bin/perl to a new major version
would cause the next "make" command to fail, since perl.mak has
hardcoded paths to perl library paths retrieved from its first run.

Now the logic added in commit ee9be06770 ("perl: detect new files in
MakeMaker builds", 2012-07-27) is extended to regenerate
perl/perl.mak if there's any change to "perl -V".

This will in some cases redundantly trigger perl/perl.mak to be
re-made, e.g. if @INC is modified in ways the build process doesn't
care about through sitecustomize.pl, but the common case is that we
just do the right thing and re-generate perl/perl.mak when needed.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-03-29 09:48:13 -07:00